First Derivatives, the Newry-based technology firm, made a pre-tax profit of £7.6m on turnover of £105.6m in the first half of 2018.
That equates to 20% annual growth on both measures.
The company makes software used mainly by investment banks and other financial institutions.
It has also diversified into new markets like marketing technology, gaming and the automotive industry.
Chairman Seamus Keating said the "pace of major contract wins" along with high levels of repeat business position the group to continue achieving strong growth.
First Derivatives employs 2,400 people across its global operations.